Release 2.7.3.1: harden proxy recovery, updates and local API.

Restore orphaned system proxy after crash, require update SHA-256, add macOS /api auth token, fix UDP ping false positives, HTTPS-only subscriptions, and keep the UI responsive during connect.

Co-authored-by: Cursor <cursoragent@cursor.com>

dist/update.json

@@ -1,6 +1,6 @@
 {
-  "version": "2.7.2",
-  "notes": "Navis 2.7.2+2: иконка приложения (N), macOS AppIcon; обновление только по кнопке.",
+  "version": "2.7.3",
+  "notes": "2.7.3+1: восстановление system proxy после crash; auth для macOS /api; обязательный SHA обновлений; fix UDP ping; HTTPS-only подписки; UI без зависания на connect.",
   "platform": "windows-amd64",
   "os": "windows",
   "arch": "amd64",
@@ -16,7 +16,7 @@
     },
     "darwin-arm64": {
       "url": "https://git.evilfox.cc/test2/navi/raw/branch/main/dist/navis-release/darwin-arm64/Navis",
-      "sha256": "0a6d7297e132f9835e2b82f5f28ec1d4e2a51fc070343f8c701e019ac57a2e86",
+      "sha256": "847fe952e6d1dfb83bb74661accbbe2c6df0f4261a4c0619c0e20e0a7faae3ca",
       "os": "darwin",
       "arch": "arm64",
       "dmg_url": "https://git.evilfox.cc/test2/navi/raw/branch/main/dist/navis-release/darwin-arm64/Navis.dmg",